Electrical conductivity meters are used to measure what in a solution, and how should they be calibrated?

• A. They measure pH; calibrate daily.
• B. They measure temperature; calibrate weekly.
• C. They measure electrical conductivity; calibrate daily.
• D. They measure color; calibrate monthly.

Answer: (C)

Electrical conductivity meters are used to gauge how well a solution conducts electricity, which is driven by the number and mobility of dissolved ions. Because electrode response can drift over time and with temperature changes, calibration is essential to keep readings accurate. The standard approach is to calibrate with a known conductivity solution at a defined reference temperature (often 25°C) so the meter can be set to the exact, published value. Many meters have automatic temperature compensation, but you still calibrate to ensure the system is reading correctly under the conditions you’re measuring. Daily calibration is a common best practice in labs that require reliable, routine measurements. After calibration, rinse the probe between solutions and store it according to the device’s guidance. This device isn’t used for measuring pH or color, which are measured by other kinds of meters.